Several approaches to mammographic imaging have been investigated in the last two decades in the hope of optimizing the detection and characterization of breast cancer at an early stage. Due to imaging limitations, however, only two of the detection methods (film/screen combinations and xeromammography) have been used extensively for this purpose. Both have significant advantages as well as distinct limitations. The purpose of this project is to carry out a comprehensive feasibility study to investigate a digital mammographic imaging system which will combine many of the advantages of the file/screen and xeromammography approaches while eliminating many of their limitations. As a part of this investigation we shall modify a digital moving slit radiography system which is based on self-scanning solid-state diode arrays fiberoptically coupled to a mammographic fluorescent screen. When the latter phase is completed, comprehensive comparative phantom studies to evaluate the relative merits and limitations of digital mammography will be performed. Since joining the imaging research group in 1984, Dr. Rosenthal has been shifting some of his research activities into digital imaging, an area which this group has been investigating for many years. He has been working in particular with the linear digital diode array system and has become particularly interested in developing a low-dose digital imaging technique for the detection of breast cancer.